Method of forming pressure sensitive tape



Jan. 21, 1958 V D. E. RUECKERT ,8

METHOD OF FORMING papssum: SENSITIVE TAPE- Filed Nox v. 19, 1954 1 figINVENTOR.

g l 9:6 BY

ATTORNEY rted tat Dean E. Rueckert, Mokena, lll., assignor to Swift &Company, Chicago, 111., a corporation of Illinois Application November19, 1954, Serial No. 469,903

5 Claims. (Cl. 154-125) The present invention is directed to double-facepressure sensitive tape, a method of forming the tape and suitableapparatus for carrying out such a method. More specifically, the presentinvention is directed to the formation of a double-face pressuresensitive tape having adhesive coatings applied on both faces thereofand provided with sectionalized, readily removable cover tapes for bothfaces to protect the adhesive coatings prior to the use of the tape. Thepresent invention also includes a particular method of forming the tape,applying the cover tape thereto and sectionalizing the tape. presentinvention further includes a form of apparatus suitable for carrying outthe method of the present invention.

Many uses exist for pressure sensitive tape which is suitable forlaminating material. For example, in the packaging industry, it has beenfound highly advantageous to be able to apply packaging materialdirectly to the surface of the products being packaged. Such isparticularly true where transparent packaging material is utilized. Aspecific example of such a procedure is that of covering the exposedsurfaces of ham sections which have been newly cut. The meat retailercan better display his products by exposing a cut surface of meat to hiscustomers, thereby visually demonstrating to his customers the qualityof his products. This is particularly true where hams are divided intosections. The exposed surface of the meat of the ham should properly beprotected while on display. Normally, transparent wrapping material isapplied to the freshly cut surface and fastened by various means to therind or fat of the ham. Difficulties have been experienced in attachingthe wrapping material to the outer surface of the ham. Pressuresensitive tape has been used to draw the wrapping material close againstthe exposed surface of the ham and thereby preserve its freshness but,in using conventional pressure sensitive tape, having only a singleadhesive coated surface, the wrapping process cannot be neatly andetdciently carried out.

It is, therefore, proposed to form a double-face pressure sensitive tapehaving adhesive deposited on both faces and The atent having cover tapepositioned on the adhesive coatings to protect the adhesive coatingsprior to the use of pressure tape. The cover tape is sectionalized andthe abutting ends of each section extend parallel to one another out ofcontact with the adhesive coatings, thereby allowing easy removal ofeach section. The proposed method of forming such a tape as heretoforedescribed is capable of efficiently forming the tape with thesectionalized cover tape as integral parts thereof. This method includesthe forming of inverted U-shaped loops in the cover tape during theapplication of the cover tape to the adhesive coated surfaces of thebase tape. By forming the loops so described, the cover tape may bereadily sectionalize-l and each section readily removed. The methodprovides for continuous formation of the tape and no intermediate or.subsequent operations are necessary.

The advantages of such a pressure sensitive tape include convenientstorage of the doubly coated tape in the form of rolls without the tapeadhering to adjacent segments of tape and the fast and efficientapplication of the tape to two distinct and separate surfaces tolaminate the surfaces. Such advantages are readily apparent in the useof the tape of the present invention in attaching wrapping material tofood products as previously described. By applying one surface of thedoubly coated tape to the food product and the other surface to theinner surface of the wrapping material, proper seal can be maintainedabout the wrapping material and the exposed surface of the meat can beproperly protected while still capable of being observed. In otherwords, in a specific application where a ham butt is removed from themain portion of the whole ham, the exposed surface of the butt can bedisplayed and protected by applying to the surface a transparentpackaging material and laminating the edges of the packaging material tothe sides of the ham butt by the use of the pressure tape of the presentinvention. Such a wrapping can be readily accomplished with littleeffort and an adequate seal can be maintained between the wrappingmaterial and the product, thereby aiding in maintaining the freshness ofthe product.

Distinct advantages arise in utilizing the apparatus of the presentinvention in forming the pressure tape described above. As will besubsequently described, the apparatus is relatively simple inconstruction, inexpensive in operation and maintenance, and highlyemcient. This apparatus includes novel features residing in a loopforming bar having a cutting blade housed therein which operates inconjunction with associated camming surfaces of the apparatus tosectionalize the cover tape after the tape has been supplied to thecoated surfaces of the base tape. Loops are formed at spaced intervalsby the bars along the length of the cover tape and the loops aresubsequently split by action of the bars to allow the removal of theloop forming bars from close association with the inner surfaces of thecover tapes and the adhesive coatings.

Other advantages and purposes of the present invention will becomeapparent from the following detailed description made in conjunctionwith the drawings.

In the drawings:

Figure 1 is a side elevation of a section of the doubleface pressuresensitive tape of the present invention having the loop formers inoperative association with the tape.

Figure 2 is a sectional view of the double-face pressure sensitive tapeforming apparatus further showing the operation of the loop formers andtaken along line 2-2 of Figure 5.

Figure 3 is a top view in detail of one of the loop formers of thepresent invention.

Figure 4 is a side elevation of the entire apparatus of the presentinvention.

Figure 5 is a top view of a portion of the apparatus further disclosingin detail the operation of the loop formers and taken along line 5-5 ofFigure 4.

Figure 6 is a schematic showing of the operation of the camming barsforming a part of the apparatus of the present invention.

In Figure 1, a portion of a finished double-face pressure sensitive tapeis shown as comprising a base tape 10 having two surfaces coated withlayers of adhesive material 11. Positioned on the adhesive layers 11 arecover tapes 12. As shown in Figure 1, the cover tapes are sectionalizedand between the adjacent ends of the two sections shown of both the topand bottom tape are loop formers 13. These loop formers orsectionalizing means 13 operate to form'tabs 14 on the adjacent endsformers or bunching means 13 are mountedcnchaim which are partiallycovered by chain guards .175, and which comprise spacers 17 and chainlengths 18. The, chain lengths 18 directly support the loop formers 13which extend through an open side in. chain guards 16. The loop formers13 have a slotted portion 19 as can be more clearly seen in Figure 3,.Housed within this slotted portion 19 is a blade 20 which is mounted onshaft 24 and is capable of moving to a raised position as shown by thedotted lines 21 in Figure 2 and a lowered position as shown by thedotted lines 22 in the same figure. In Figure 3, spring 25 is suitablyattached to the loop former 13 and the shaft 24 to urge the blade20within the slotted portion. 19 and ,into its lowered positiondesignated by the dotted lines 22 in Figure 2. a

In the operation of theloop formers in conjunction with the formation ofthe double-face pressure sensitive tape, reference is made to Figure 4wherein the entire assembled apparatus is shown. This apparatusincludesa suitable frame 26, which is schematically shown .on which issuitably mounted a base tape supply roll 27v and adhesive applier 28,sprockets 29, 30, 31, 32'and cover tape supply rolls 34. Supply roll 27is mounted on shaft 49 while the sprockets 29, 30, 31, and 32 aremounted on shafts 50, 51, 52 and 53 respectively. These shafts aresuitably journaled in frame 26 while the, adhesive applier 28 issuitably supported by frame 26. The cover tape supply rolls 34 aremounted on shafts 50 and 51 along with sprockets 29 and 30. The rolls 34are positioned so as to be mounted over or under the path of movementalong which the tape is formed. The upper cover tape supply roll 34mounted on shaft 59 is positioned ahead of sprocket 29% the latter ispositioned to'the far side of the path of movementof the'base tape 10.Similarly, sprocket 30 is positioned, on the near side of'the path ofmovementand, therefore, the cover tape supply roll mounted on shaft 51is mounted behind sprocket 3.9. Thus, the cover tape supply rolls 34arepositioned so as to supply cover tape in the same vertical plane as thebase tape during the lattersmovement through the apparatus Mounted onthe sprockets. 29; and 31 is an upper chain conveyor. 35. 7 A lowerchain conveyor 36 is similarly mounted on, sprockets 30 and 32. Theframe ,26 also supports a motor 37 which operates drive belts 39, 40 and41. The drive belt 39 extends from the motor 37 to the sprocket 32 abouta pulley 54 mounted on shaft 53 while the drive belt 40 extends betweenthe pulley 54 anda pulley 55 mounted on shaft 52. The drive belt 41operates. between the motor 37 and a collecting roll and tensionsupplying roll 42 which is mounted on shaft 56. The belt 41 extends topulley 57 also on shaft 56 which is suitably journaled in frame 26. Alsomounted on frame 26 are pressure means 44 which include springs 45 androlls 46. These pressure means 44 are of conventional design, the rolls46 being resiliently urged toward the assembled tape by the springs 45.Additional. features of the apparatus shown in Figure 4 include the cams47 and 43 which are hidden in Figure 4 but which can be seen in the viewshown in Figure 5. Cams 47 and 48 are suitably mounted on frame 26between the upper and lower chain conveyors 35 and 36 to cooperatewith.the protruding ends of the blades mounted within the slottedportions 19 of the loop formers 13. The cams 47 and 48.wil1 be morethoroughly described subsequently.

In the' operation of the apparatusa s described, atten tion isdirectedto Figure 4 wherein it can be seen that the motor 37 suppliespower through bel t;39 tosprockets one 31 in a counter clock-wisedirection and the -lower one 32 in 'a clock-wise direction. Upper andlower chain conveyors 35 and 36 are moved in the same direction as theirrespective sprockets. This rotation of the sprockets 31 and 32 in turncauses the sprockets 29 and 30 to rotate in a similar manner therebyrotating the cover tape supply rolls 34 Whichare associated therewith.The base tape 10 is fed from base tape supply roll 27 by the rotation ofthe tension supplying and tape receiving roll 42 which is rotated inaclock-wise direction by belt 41. As the base tape 10 advances from thebase tape supply roll 27, an adhesive is supplied to either one or bothof the surfaces of the tape by the adhesive applier 28, which isshown,schematically. This applier'is of of conventional design and isnot shown in any great detail. The base tape'lfl advances into contactwith the loop formers 13 which are mounted on the upper and lower chainconveyors 35 and 36 respectively, as previously described in connectionwith Figure 2. The loop formers 13 contact, the adhesive coating on bothsurfaces and maintain this contact with thecoatedbase tape as the latteradvances through the apparatus. -Fol lowing the contact of the loopformers 13 :with the coated base tape 10, cover tape 12 is introducedinto contact with the coated surface of base tape 10 and the loopformers 13. The association of the cover tapeis brought about by thefeeding of the cover 'tape 12 from the cover tape supply rolls 34 aspreviously described: The close association of the cover tape 12 withthe adhesive surfaces of the base tape 10 is brought about by thepressure meansi44. These pressure means include the rolls 46 which areyieldingly forced against the cover tape by means of springs 45. Thesprings allow the rolls to yield to the loop formers when the loopformers are passed between the rolls. The pressure means there by bringthe cover tapes 12 into close'associationwith the loop-formers 13. As aresult, a loop or inverted U is formed in the cover tape having the loopformers embedded within the loop. As the loop formers 13, cover tapes 12and base tape 10 advance, the cams 47 and 48 operate to move the blades20 within the loop formers 13 out of the slots 19 to cut the loops andthereby sectionalize the cover tape and free the loop formers 13 fromthe loops. The manner in which this isiaccomplished can be readily seenin the diagrammatic view of Figure 6 wherein the cams 47 and 48 areshown in operative position which is somewhat exaggerated .so as to moreclearly illustrate. the camming operation. There are two cams, one ofwhichis tilted upwardly while the other is tilted downwardly. The upper47 is positioned (see Figure 5) to operate the loop formers 13 attachedto the upper chain conveyor 35 while the cam 48 operates the loopformers 13 attached to the lower chain conveyor 36'. As previouslystated, the blades 20 housed in the slotted portions 19 of the loopformers 13 are urged by springs 25 into the slotted portion. The ends ofthe blades 20 extend beyond ,the body of the loop formers and cooperatewith the cams 47 and 48 when contact is made. As the loop formers 13advance, the angled earns 47 and 48 operate to raise the blades 20against the springs 25 by contac'tingthe ends thereof. The blades 20rotate about the shafts24 and eventually reach the raised position shownby the dotted'lines 21 in Figure 2. Upon reaching this positiontheblades sever the portion ofthe cover tapes directly above them so asto divide the cover tapes into sections. Following the severingoperation, the loop formers 13 are free to move out of contact withthecover tape 12 and the adhesive coated base tape 10. This isaccomplished by the reaching of the end of'the run by the loop formersand the raising or lowering of them, depending on the conveyor beingobserved by the sprockets 40.and 39; Meanwhile, the finished double facepressure sensitivetapeis collected on'the tension supplying and tapereceivingroll 42. "The adjacent ends 14 of each section of the covertape are-flattened by-the rolling up-:of'the a tape on the roll 42 butare sufiiciently long to remain free from contact with the adhesivecoatings on the base tape 10. The freedom of these tabs 14 allow readyremoval of each section of cover tape upon subsequent use of thepressure sensitive tape.

The shape of the loop formers 13 may vary depending on the amount ofspace desired between the tabs 14. As shown in Figure 1, the loopformers 13 are oblong in shape. The thickness of the loop formers 13 andthe distance between the tabs 14 are somewhat exaggerated in Figure l tobetter show in detail the type of loops formed in the cover tape 12. Thespacing of the loop formers 13 along the upper and lower chain conveyors35 and 36, respectively, may obviously vary depending upon the length ofcover tape sections desired. The adhesive coating may be applied solelyto one surface of the base tape, if so desired. The apparatus of thepresent invention is fully capable of forming a single sided pressuresensitive tape. In referring to Figure 4, it can be readily seen thatthe cover tape supply roll 34 associated with the sprocket 39 may betaken out of operation and the apparatus operated as previouslydescribed with the exception that only a single surface, in thisparticular instance the top surface, of the base tape 10 being coatedwith adhesive.

The apparatus of the present invention is fully capable of automaticallyforming a double-face pressure sensitive tape having sectionalized covertape applied to the coated surfaces thereof. Such a tape can be readilystored on rolls and easily removed therefrom without adherence havingoccurred between the layers of the tape on the roll. Such a tape can beefficiently applied to laminate surfaces as the sectionalized cover tapeon both faces of the pressure tape can be readily removed.

Obviously, many modifications and variations of the invention ashereinbefore set forth may be made without departing from the spirit andscope thereof, and therefore only such limitations should be imposed asare indicated in the appended claims.

I claim:

1. A method of forming pressure sensitive tape which comprises: coatinga surface of a flexible tape with adhesive, depositing cover tape onsaid surface, bunching said cover tape at spaced intervals during thedepositing thereof, and thereafter dividing said cover tape at thebunched intervals into sections.

2. A method of forming double-face pressure sensitive tape whichcomprises: coating at least two surfaces of a flexible tape withadhesive, depositing covering material on the coated surfaces, loopingsaid covering material to form an inverted U at spaced intervals duringthe depositing thereof, and thereafter dividing said covering materialinto unconnected sections by separating each inverted U into twosegments.

3. A method of forming pressure sensitive tape Which comprises: coatinga portion of flexible tape with adhesive, depositing a covering on thecoated portion, looping the covering to form an inverted U at spacedintervals during the depositing thereof, and thereafter dividing saidcovering into sections by separating each inverted U into segments.

4. A method of forming pressure sensitive material which comprises:coating a surface of a base material with adhesive, depositing coveringmaterial on the coated surface, bunching said covering material to forman inverted U and thereafter dividing the inverted U at a point alongthe arcuate portion thereof.

5. A method of forming double-face pressure sensitive tape whichcomprises: coating at least two surfaces of a flexible tape withadhesive, depositing covering tape on the coated surfaces, bunching saidcovering tape to form an inverted U at spaced intervals during thedepositing thereof, and thereafter dividing each inverted U into twosegments at a point along the arcuate portion thereof.

References Cited in the file of this patent UNITED STATES PATENTS2,050,191 Liebowitz Aug. 4, 1936 2,292,024 Dreher Aug. 4, 1942 2,303,087Neller Nov. 24, 1942 2,414,739 Heygel Jan. 21, 1947 2,552,664 BurdineMay 15, 1951 2,560,566 Graves July 17, 1951 2,688,582 Phair Sept. 7,1954

1. A METHOD OF FORMING PRESSURE SENSITIVE TAPE WHICH COMPRISES: COATINGA SURFACE OF A FLEXIBLE TAPE WITH ADHESIVE, DEPOSITING COVER TAPE ONSAID SURFACE, BUNCHING SAID COVER TAPE AT SPACED INTERVALS DURING THEDEPOSITING THEREOF, AND THEREAFTER DIVIDING SAID COVER TAPE AT THEBUNCHED INTERVALS INTO SECTIONS.